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Intersection Treatments
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Module C
INTERSECTION DESIGN TREATMENTS
Designing for Bicyclist SafetyModule C
LEARNING OUTCOMES
Understand intersection design options and features
Select appropriate design feature for a bikeway in a given context
KEY SAFETY FACTORS
Speed Number of lanes Visibility Traffic volume & composition Conflict points Proximity Bike control Connectivity
Designing for Bicyclist Safety
SHARED-USE PATH CROSSINGS
SIDE-STREET CROSSINGS MID-BLOCK CROSSING DESIGN PROCESS
Geometric alignment & terrain considerations
Roadway characteristics (lane, speed, volumes)
Evaluate sight triangles
Determine which leg has priority
Assess potential crossing treatments
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SIGHT TRIANGLES PATH YIELDS TO ROADWAY
ROAD YIELDS TO PATHWAY
Crossing Countermeasures Advance warning signs Advance yield/stop line Raised island/crossing RRFB/PHB
BIKE “HAWK” PHB First installation Tucson, AZ “BIKES WAIT”/”BIKES OK”
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Normal PHB with Bike Facilities and R9-5 for cyclists to use pedestrian signals
BIKEHAWK AT PHB CROSSINGS BIKE TOUR
Where were you comfortable? What made you uncomfortable? What bikeway features worked? What bikeway features could be improved?
Designing for Bicyclist Safety
INTERSECTION DESIGN
INTERSECTION DESIGN PRINCIPLES
Reduce speed Minimize exposure to conflicts Communicate right-of-way priority Provide adequate sight distance
INTERSECTION CONFLICTS
Typical conflicts for both pedestrians and motorists, plus:Right-turn/thru
movementWeaving to left turn
Albuquerque, New Mexico
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Albuquerque, New Mexico
RIGHT-TURN/THRU CONFLICT
LEFT-TURN CONFLICT
Madison, Wisconsin
RIGHT-TURN COUNTERMEASURES
SHOULDER RIDING AT INTERSECTION
Shoulder not a travel lane Modify shoulder striping Opportunity to switch to shared lanes OR Add bike lane thru intersection
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SHOULDER STRIPING INTERSECTION WITH SHARED LANES
Additional/all lanes are shared at intersection
BIKE LANE THRU INTERSECTION BIKE LANE THRU INTERSECTION
HIGHLIGHT CONFLICT ZONE
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HIGHLIGHT CONFLICT ZONE BIKE LANE THRU INTERSECTION
BIKE LANE THRU INTERSECTION BIKE LANE THRU INTERSECTION
SHARROW W/ GREEN BACKGROUND IS THIS CONSISTENT WITH MUTCD?
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IS THIS CONSISTENT WITH MUTCD? RIGHT TURN SHARED LANE
RIGHT-TURN SHARED LANE
Madison, Wisconsin
INTERCHANGE RAMPS
Recommended Design Guidelines to Accommodate Pedestrians and Bicycles at Interchanges
ITE 2016
(#)
GUIDING PRINCIPLES FOR PEDESTRIANS
Ramp geometry Locate crosswalk
Best visibilityBefore accelerate
Crosswalk short w/out excessive deviation
Widen sidewalks shared with bicyclists
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GUIDING PRINCIPLES FOR BICYCLISTS
Buffer where bicyclists are between moving vehicles more than 200 ft
Provide bike “exit” option ahead of on-ramps Define a weaving area
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LEFT-TURN COUNTERMEASURES
TWO-STAGE LEFT TURN BOX TWO-STAGE LEFT-TURN QUEUE BOX
Required design elements include:Bicycle symbol Turn or through arrow Turn on red prohibition Passive detection of bicycles
Size to prevent conflicts
BIKE BOX BIKE BOX
Reduced conflicts between bicyclists and turning vehicles
Reduced avoidance maneuvers Reduced encroachment into crosswalks Use clearly understood by motorists and
bicyclists
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BIKE BOX
Required elements: Advance stop line at 10’ Bike symbol in the box RTOR prohibited Setback from crosswalk 50 feet of bike lane on approach STOP HERE ON RED (R10-6/R10-6a) with EXCEPT
BICYCLE text plaque Countdown ped signal if box crosses multiple lanes Yellow change & red clearance
Green pavement is optional
BIKE BOX
BIKE BOX
Designing for Bicyclist Safety
TRANSITIONS
CONSIDERATIONS
What happens at termini? What happens when bicycle facility type
changes? Have you stranded or created a barrier to the
less confident user? How many stops will bicyclist have to make to
traverse transition?
into a two-way separated bike lane
EXAMPLE TRANSITIONS
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into a conventional bike lane
EXAMPLE TRANSITIONS TRANSITION AT TERMINI
San Juan, PR
SHARED-USE CROSSING
San Juan, PR
ACCESS TO/FROM SIDE STREET
ACCESS TO/FROM SIDE STREET
Atlanta, GA
ACCESS TO/FROM SIDE STREET
Atlanta, GA
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Module C
ACCESS TO/FROM SIDE STREET
Atlanta, GA
STEEP GRADE TO INTERSECTION
Atlanta, GA
STEEP GRADE TO INTERSECTION
Atlanta, GA
Designing for Bicyclist Safety
SIGNALIZED INTERSECTIONS
SAFER SIGNALS FOR BICYCLISTS
Bikes start-up and travel slower than carsDifferentiating bike detection to optimize signals Set initial and gap times to accommodate bikes
Leading Bike Interval Segregate Conflicting
Movements
BICYCLE SIGNAL FACE
Application for: Bicyclist non-compliance Provide a leading or lagging bicycle
interval Continue the bicycle lane on the right-
hand side of an exclusive turn lane Augment the design of a segregated
counter-flow Unusual or unexpected arrangements
of the bicycle movement through complex intersections, conflict areas, or signal control.
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BICYCLE DETECTION
Buttons Loops Video Microwave Radar Infrared
Grand Prairie, Alberta
PUSH BUTTONS
LOOP DETECTION
Portland, OR
PASSIVE DETECTION
5-71
MUTCD standard for signal loop marking for bicyclists
(Section 9C.05)Designing for Bicyclist Safety
BICYCLISTS AT ROUNDABOUTS
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MAKING ROUNDABOUTS WORK
Slow speedsDeflection Truck apronNO BIKE LANES
Simple Single laneNO BIKE LANES
Splitter islands Escape ramps
Bike Walk Encinitas
Bike lane ends at splitter island
Bend, Oregon
Bend, Oregon
Slower speeds and fewer conflict pointsBend, Oregon
Slower speeds and fewer conflict points
Bend, Oregon
Bike lane begins
Bend, Oregon
Escape ramp
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BIKEWAY MARKINGS AT ROUNDABOUTS “PROTECTED” INTERSECTIONS
photo source: People for Bikesphoto source: Google
Austin, TX Davis, CA
Salt Lake City, UT Chicago, IL
photo source: Streetsblogphoto source: WBUR
“PROTECTED” INTERSECTIONS
motorist’s view at conventional bike lane
motorist’s view at separated bike lane
VISIBILITY AT CONFLICT POINTS
photo source: Jonathan Maus
protected intersection conventional bike lane
VISIBILITY AT CONFLICT POINTS
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Corner refuge island1
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Motorist yield zone
Pedestrian crossing island
Forward bicycle queuing area
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Pedestrian crossing of separated bike lane
Pedestrian curb ramp5
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PROTECTED INTERSECTIONS
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Vehicular turning design speed
Minimum approach clear
space
<10 mph 20’
10 mph 40’
15 mph 50’
20 mph 60’approach
clear space
APPROACH CLEAR SPACE
• Maximum taper 3:1
• Bend-out preferred (motorist yield zone, bus stops, pedestrian refuge area, loading and parking)
• Separation increases sight distance
• Corner island affects motorist yield zone
bend-inbend-out
DEFLECTION
• Design for ≤10 mph vehicle turns
• Mountable truck apron
• 3” max.
• Visually distinct
• Large radii reduces bicycle, pedestrian queuing areas
SLOW RIGHT TURNING SPEEDS ADA ISSUES
PROWAG was written over 15 years ago Still a “draft” but widely used and enforceable Did not consider SBL’s Must be interpreted
NO EASY ANSWERS
Signal Phasing Overview
time separation from motor vehiclesnone full
Concurrent bike phase with concurrent permissive vehicle turns1
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Concurrent protected bike phaseProtected bike phase
Concurrent bike phase with leading interval
1 2 3 4
Concurrent Bike Phasewith Concurrent Permissive Vehicle Turns
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showing phase
1 2
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Concurrent Bike Phase with Leading Interval
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showing phase
1 2 3 4
Concurrent Protected Bike Phase
1 2 3
showing phase
3
Concurrent Protected Bike Phase
1 2 3 4
showing phase
4
Protected Bike Phase
3
showing phase
1 2 3
Protected Bike Phase
4
showing phase
1 2 3 4
No Turn on Red Restrictions
Consider at:
• Two-stage queue box
• Two-way SBL
• Contra-flow SBL
• Protected bike phase
• Protected right turn
• Leading bike phase
• Bike boxes
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Signal Head Positioning
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Bike signal (near side)1
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Pedestrian signalVehicle signal
Bike signal (far side)
Signal Positioning
one-way SBL two-way SBL
Bicycle Detection
• Actuated signals
• Bicycle minimum green
• Protected bicycle phases
100’ for advanced detection
typical locations
Designing for Bicyclist Safety
SUMMARY THOUGHTS
CHICAGO, IL CHICAGO, IL
Intersection Treatments
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Module C
CHICAGO, IL